May 7 (UPI) — Carnivores living in captivity mate and give birth to offspring each year at the same time as their relatives living the wild, according to new research by scientists at the University of Zurich.
Reproduction patterns ensure the arrival of the next generation of offspring coincides with favorable weather and food abundance. But in zoos, food is plentiful year round and temperatures are always tolerable.
When researchers analyzed data on more than 150,000 births in dozens of zoos, involving 100 different carnivore species, they found patterns mirroring the reproductive schedules of wild animals.
“It is surprising how closely the zoo data correlates with that from animals in their natural habitat,” UZH zoologist Marcus Clauss said in a news release.
The research, published in the Journal of Biological Rhythms, found 80 percent of carnivores mate and give birth at the same time every year whether they’re living in the zoos or in the wild.
“Seasonality is an evolutionary feature and thus a fixed characteristic of a species — most probably through a genetically determined reaction to a signal given by the length of daylight,” Clauss said.
Researchers found species living farther from the equator are more likely to stick to a seasonal reproductive pattern, but the sea otter bucks the trend. Scientists believe the year-round of availability of mussels and sea urchins allows for the otter’s irregular reproduction.
“It’s fascinating to see how little reproductive seasonality is influenced by the conditions in a zoo, where enough food is available all year round, and therefore how the data from zoo animals can be used to describe species’ biology,” said Clauss.